Solid state light emitters are used in a variety of lighting components in, for example, commercial, automotive, and consumer lighting applications. Solid state emitters can comprise, for example, one or more unpackaged light emitting diode (LED) chips, and/or one or more packaged LED chips, wherein the chips can comprise inorganic and/or organic LED chips (OLEDs). Solid state emitters generate light via the recombination of electronic carriers (electrons and holes) in a light emitting layer or region of an LED chip. LED chips have significantly longer lifetimes and a greater luminous efficiency than conventional light sources. LED chips are also environmentally friendly unlike conventional metal halide bulbs. However, as LED chips are narrow-bandwidth light emitters, it can be challenging to simultaneously provide good color rendering and uniformity in combination with high luminous efficacy while maintaining and maximizing brightness and efficiency.
Lighting designers, manufacturers, and/or consumers have expressed the need for an alternative to and/or a replacement for costly and environmentally toxic ceramic discharge metal halide (CDMH) bulbs. CDMH bulbs also disadvantageously require a warm up time before emitting light, which is bothersome to consumers.
Challenges exist in incorporating solid state lighting sources into high output fixtures such as spot light, high-bay, and/or low-bay lighting applications, for example as found in retail locations where CDMH lighting has been used. Conventional solid state components utilize large form-factor diffusers that are placed either close in proximity to and/or directly on the light emitting chips, which results in color separation, color blotches, and/or color rings. Challenges exist in obtaining a uniform color and light output from solid state lighting fixtures.
Accordingly, room for improvement exists in providing solid state lighting components that exhibit improved color rendering, improved color uniformity, and improved directional lighting, and that are also suitable for use in high output lighting applications and can be used in place of CDMH bulb lighting.